Where—
(a) the Secretary of State is satisfied on an application made to him by a local authority or a development corporation or a housing association with respect to a house which they have provided that the cost of providing the house has been substantially enhanced by reason of either or both of the following matters, namely—
(i) that, with his consent, the house has been constructed in whole or in part by an experimental method;
(ii) that, with his consent, materials have, for the purposes of experiment, been used in the construction of the house or equipment or fittings have, for those purposes, been installed in the house in the course of the construction thereof; or
(b) with the consent of the Secretary of State, expense is incurred by a local authority or a development corporation or a housing association in incorporating or installing in a house, otherwise than in the course of the construction thereof, materials, equipment or fittings for the purposes of experiment;
then, subject to such conditions (if any) as the Treasury may determine, the Secretary of State may make to the local authority or development corporation or housing association, as the case may be, an Exchequer contribution or Exchequer contributions of such amount and payable in such manner as he may determine.